Lubricating device



Sept. 14, 1937. I y vH. TEAR 2,093,386

LUB'RICATING DEVICE Filed-June -1l. 1954 f 2 Sheets-Shea@ 1 IN VEN TOR.

HHPPY .Q T599. #.2 BY

A TTORNEY Patented. Sept. 14, 17,937l

LUBRICATING DEVICE Harry R. Tear, Evanston, Ill., assgno to The Lubrication Corporation, Chicago, Ill., a corporation of Delaware Application June 11, 1934, Serial No. 730,016

11 Claims.

This invention relates to improvements in lubricating devices 'and more particularly to pistons and piston packing for lubricant containers and cartridges wherein a piston comprises one of the lubricant 'conning walls of the container or cartridge. y In the distribution and use of lubricant, in interchangeable cartridges, for lubricant guns, or

other lubricant dispensing apparatus, it is de-H sirable that the cartridge be constructed of cylindrical form and be provided with a piston, comprising o ne of the confining walls of the cartridge lubricant containing space, so that the piston may move along the inner walls of the cylindrical containeror cartridge either under atmospheric pressure or under. force applied to the` rearwardface of the piston, thereby to assure of the discharge of all of the lubricant 4contents fro'm the cartridge. Such a-piston, in order to operate properly, must have lubricant-tight sealing engagement with the inner cartridge walls so that air may not be admitted into the lubricant confining space, and conversely to preclude the leakage of lubricant past the piston particularly in such cases as where the piston is urged 'inwardly of the cartridge under pressures greater than atmospheric pressure.'

An object'of my invention is to provide a lubricant container, or cartridge, of the character described incorporating a novel cartridge piston packing means having relatively high resiliency thereby readily to conform to the inner walls of the cartridge regardless of slight irregularities of wall surface such as vcaused by the presence of overlapping or lock-seams or as a result of variations in internal cartridge wall diameters.

Another object is to provide a cartridge of the character described including a piston having a packing ring of material, such as rubber, normally subject to damage by contact with ordinary greases or lubricants, wherein novel means are employed to protect the packing from direct contact with the grease or lubricant contents of the cartridge. A'further object is to provide a cartridge piston having a. packing so constructed as to provide increased sealing function Aduring the normal advance movement of the piston along the axis of the cartridge, as during the discharge of the contents thereof.

Other objects, the advantages, and uses of the invention will be, or should become, apparent after reading the following speciiication and claims and after consideration of the drawings 55 forming a part of the specification, wherein (C1. azi-47.3)

Fig. 1 is a partial sectional view of a lubricanta cartridge constructed in `accordance with the invention;

Fig. 2 is a fragmentary sectional view of a part of the cartridge of Fig. 1; 5

Fig. 3 is a perspective view of the packing ring of the cartridge piston; I

Figs. 4 to 6 inclusive are views, similar to Fig. 2, illustrating other forms of the piston and piston packing; I l y, 10

Fig. '7 is an enlarged sectional view of the piston packing of Fig. 6; and

Figs. 8 to 15 inclusive are views, lsimilar tof' Fig. 2, each illustrating another form of the pis-Y ton and piston packing structure. l5

In Fig. 1 I have illustrated Aa typicalform of interchangeable lubricant cartridge such as for- -use with hand lubricant guns which comprises,

`a hollow sheet metal cylinder 2 having' an yend 'closure at its forward end formed of a stamping 20 -3 secured to the cylinder as byla folded seam 4 a sheet metal piston 5 slidably mountedpwithin the cylinder 2 and forming a rear closure for the cylinder thereby to provide a lubricant confining space 6 between the closure 3 and piston .5. 25 Anoutlet opening 1 may be formed centrally of the enclosure 3, the walls 8 of which may be fashioned to provide sealing engagement with the cartridge connector stud of a lubricant gun or other lubricant feeding device with-which the 30 cartridge is to be used. In the cartridge illustrated, the wall 8 is concave and spherical. Bayonet lugs 9 may be formed in the seam 4 to serve4 as an attaching means for providing quick attachment and detachment of the cartridge to 35 and from the aforesaid gun or dispensing device. Subsequent to the installation of the piston 5 with'in the cylindrical body of the cartridge, abead II may be formed on the rearward end of the cylinder 2 thereby to `retain the piston within 40 the cartridge during shipment, vto stien the body and to avoid exposing the sharp edge, which would be objectionable in handling the cartridge. My invention relates particularly to the piston and piston' packing means and contemplates the 5 provision of a pliant packing ring I2, preferably of soft rubber, located in an annular depression I3 formed in theouter. side wall I4 of the piston 5,

and of such thickness that at least a portion of the packing extends beyond the outermostregion ofthe piston side wall to engage with the inner side wall I5 of the cylindrical cartridge body 2. c

The piston 5, selected for illustration herein,

may be formed of sheet nietal of sufficient rigide ity to maintain its preformed contour under substantially heavy thrusts applied thereto of a purely mechanical or fluid nature.. 'Ihe head I6 of the piston may be provided with a central depression II in its-outer face adapted to embrace that portion of the end closure 3 forming the outlet wall l thereby to assure of the complete ,discharge of lubricantl from within the cartridge as the piston is moved or urged inwardly thereof.

I prefer to employ a rubber band, or packing ring, I2 of a diameter less than the diameter of the side wall Il of the piston thereby to cause the packing ring closely to adhere to 'the wall' of the annular depression I3 when in place thereupon. 'The central portion of that region of the outer wall of the piston forming the depression I3 is preferably curved outwardly, as shownv at I8, thereby to-"cause the lpacking ring I2, at its mid-point, to extend beyond the side wall I4 of the piston and into close engagement with the inner sidewall I5 of the cartridge bodynthe edges I S. of the packing ringl being free of engagement with the cartridge wall. This arrangement of the packing ring provides a relatively broad surface of contact between the packing ring and piston wall Il by virtue of the elastic properties of the packing ring and a substantial zone of contact between the packing ring and cartridge side wall. the extent of which is enhanced rather than diminished as the piston is moved relative to the cylinder. is one of importance and is attributed largely to the high 'ductility of the packing ring and its susceptibility to lateral compression closely to iill the space between the piston and cartridge side wall. 4

Inasmuch as soft rubber will deteriorate when brought into contact with most petroleum'oils,

of the piston and cartridge .respectively and also on the surface of the packing ring I2. Within this class of preparations I'have found that a gel of spda-rosin and soda-hydrofol soaps in glycerine known to the trade as Plug Valve Lubricant No. 3 and sold by they Standard Oil Company (Indiana) may be used satisfactorily. 'I'his gel has the property of providing adequate lubricad tion to the surface of the packing ring to permit4 it to slide readily along the cartridge wall and its consistency is suillcient to render disposition in the manner described, both practical and lasting.y

Other preparations or gels of an oil-impervious nature may be substituted for the gel described, 'including mixtures or gels consisting of soaps In polyhydroxyl alcohols. Needlessto say, the preparation should be of a substantially neutral nature in order not to cause corrosion 'of the metal surfaces of the piston or cartridge walls.

In'Fig. 4 I have illustrated a modified form of theV piston packing of Fig.'2 wherein the deposited preparation 2 la is disclosed as located upon both sides 'of thepacking ring I2 thereby to surround, in substantial amounts, all portionsof the packing ring I2 not in direct contact with metal. In

'rms latter function of the ypacking .a deposit of the preparation upon the assembled pisto'n in the manner described. l0 In Fig. 5 I have illustrated another form of the f piston and packing which differs from that illustrated in Fig. 2 in the provisionof a second annular depression 22 in the piston side wall I l forwardly of the depression II, thereby to in- 15 crease the space within which the deposit 2| may be disposed thus to assure an ample quantity of the protective substance forwardly of the piston packing ring.

In Fig. 6, I have illustrated another form of' 20 the piston packing which differs from that Illustrated in Fig. 2 only by the elimination of the protective preparation 2i and the substitution therefor of a coating of oil-imperviousexible substance such as collodion, flexible varnish, and 25 glue-glycerine preparations over the entirepacking ring I2 as illustrated at 22. This coating.` see' Fig. 7, may be applied to the packing ring as' by dipping the ring into a bath of the protective sub-I stance andin applylnstheringtothepistonafter the coatinghassctorattaincdato pei-mit of its being mingled.

"I'heplstonsthusfai'dcsibedallpoloccltbe vadvantageous characteristi' cl attributedv thereto bythe provisionofarelativeiy'soitpa::king|ing,;V

thecentral portion ofwhichism'gedoutwardly under compresion into intimate contact with tbe innucartridgewalLandthecdgesofwhichlie withintbedepressionintheonterllstonwalland witbinadiameterlesstbanthemtddediameter oftbepistonwail Il,thustofacilitate`tbe entry ofthepistonintothecartridgeasduringamembly. Eachofthepistonsducribedincludeain addition, protective deposits4 or coatings of petroleum oil-impervious and oil-insoluble substances, thereby. separating the rubber packing from the oily lubricant contents of the cartridge to the end that a long useful life of the piston Packing is assured.

In Figs. sto 13 inclusive I have illustrated other 50 forms ofthe piston and pachngfstructure all of which includel the pliant rubber packing ring I2 of Fig. 3 and which diil'er. from one another and from the structures heretofore described in the. arrangement of the pachng ring by variation in contour and location of the packing-receiving de-v pression in the piston side wall Il. The protective deposit 2| or the protective coating 23-may be employed as desired and in the manner de' lscribed for precluding deterioration of the packing tins. l v

The piston of Fig. 8 has an annular depression 25 located adjacent the inner end or head Il of the piston including a portion '2l providing a cylindrical packing-receiving surface parallel to the 05 inner wall I5 of thecartridge body and lying inwardly from the piston side wall Il a distance less than the normal thickness of the packing ring I2. The forward portion 21 of the depression is defined by an inwardly curved surface of greater depth than the normal thickness of the packing ring. 'Ihis arrangement of the depression and packing ring, as in the piston of Figs. 1 to 6 inclusive, results in maintaining a relatively low frictional condition between packing ring and fcartridge wall without sacrifice of sealing properties and at the same time facilitates entry of the piston into the cartridge during assembly by virtue of the decreased diameter of that portion ofr the ring I2 in the portion 2'I of the depression at the leading edge of the piston. A

It is important in pistons of the type disclosed herein that the packing ring be wider than it is Y thick so that it cannot turn or roll-up as the piston moves. It is also desirable to limit the compressed portion of the packing so as to reduce ra- 'dial thrust and hence reduce frictional resistance to longitudinal movement of the piston. These features are provided by all of the pistons disclosed and in addition, as pointed out, each of the packing rings in the several forms illustrated fall away from the wall of the cartridge at one or both edges, thus to facilitate entry of the piston into the cartridge. This latter advantage is attributable to the formation and disposition of the annular depression in the outer piston Awall.

The piston and packing of Fig. 9 is identical to that illustrated in Fig. 8 except that the forward portion 21 of the packing receiving depression terminates at the inner end or head I6 of the piston whereas in the piston of Fig. 8 the piston side wall I4 ahead of the depression, as shown-at 28, remains intact and may serve asan additional guide vsurface to prevent piston canting.

is located adjacent to the rearward end ofthe.

Each of the pistons of Figs. 8 to l1 inclusive is Iintended for introduction into the cylindrical body 2 of the cartridge, subsequent to assembly of the packing ring I2 thereupon, through the rearward end of the cartridge body prior to the formation of the bead II. Continued forward vor inward movement of the pistons in each of the forms mentioned will augment the piston sealing characteristics of the packing rings I2 due to the ability of the rubber of the ring to virtually ow under lateral compression thereby to closely contact the adjacent and spaced apart walls of the cartridge body and packing receiving depression.

In Figs. 12 and 13 I have shown piston and packing assemblies which are intended to be introduced through the forward end of the cartridge body 2, as prior to securing the end closure 3 thereto. The piston of Fig; 12 is similar to the piston o() of Fig. l1 except` that the inwardly curved portion 2'I, or portion of increased depth, of .the depression 25 is located at the posterior side of the depression and adjacent to the rearward end of the piston side wall I4.

The piston of Fig. 13 represents a reversal of .the deep and shallowportions ofthe depression as disclosed in Fig. 9. v

In Figs. 14 and 15 I have illustrated pistonassemblies each incorporating a vpair of the pack- 70 ing rings I2 so arranged that one will provide increased sealing function when the' piston is nrgednin one directionl and the other increased In Fig. 1o the depression 2s, within whichxthe" of the packing arrangementsof the pistons of Figs; 13 and 11 whereas the pistons of Fig. 15 comprise a combination of the packing arrangements of the pistons'of Figs. 9 and 12.

While I have illustrated and, described various forms of the piston and packing assembly for a container or cartridgeand particularly described the pistons as constructed of sheet metal and the packing rings as comprising rubber rings, it should be understood that other materials may be employed for each of these elements without departing from the spirit or s cope ofthe invention. By way of example, the pistons may be turned from wooden blocks or constructed of moulded composition and otherpliant packing material, such as rawhide, might be substituted for the rubber bands described.

I claim:

1. A piston for lubricant cartridges, having a i substantially cylindrical side wall traversed by a circumferential depression, a portion of the bottom of said depression being outwardlycurved longitudinally, anda resilient packing ring located i-n said depression and extending substantially completely across the said outwardly curved portion thereby causing the said packing to as sume a convex form.

2. -A piston for lubricant cartridges,` having a substantially cylindrical side wall traversed by a circumferential depression, a portion of the bottonr'of said depression being outwardly curved, and a packing-ring of resilient material in'said depression and protected from contact with, the

contents of the package bya deposit of a plastic senil-solid material impervious to thev said c-on Y tents, having no harmful effect on the'material of the packing ring and -capableof lubricatingthe said packing ring to facilitate longitudinal movelably mounted in said body, said piston having a side wall extending substantially parallel with the adjacent inner side wall 'of said body and formed with a circumferential depression, a packingfring encompassing said piston side wall and lying in said depression,v and a deposity of relatively plastic material in said depression interposed between said packing and the inner end of said piston thereby to protect said packing against oontact with the contents of vthe cartridge.

4. A piston of the character described having a side wall extending substantially parallel to the longitudinal axis thereof, said side wall having an annular depression therein located in a plane transverse to said axis, the longitudinal central portion of said depression being outwardly curved, and a pliant packing ring located in said depression, the central portion of said packing ring being curved outwardly beyond the outer portion of said side wall by said outwardly curved` portion of said depression and the edges of said wall by said outwardly curved portion of said depression.

16. A piston of thecharacter described having a side wall lying substantially parallel to the longitudinal axis thereof, said side wall having an annular depression formed therein, of varying 'depth longitudinally, but of uniform sectionA circumferentially, and a packing ring of pliant material having normally nat and relatively broadside walls disposed in said depression, the thickness of said packing ring b ng such as to cause those portions disposed in t e portions of said depression of lesser depth to lie beyond the surface of said piston side wall.

'7. A piston of the character described having a side wall lying substantially parallel to the longitudinal axis thereof, said side wall having an annular depression formed therein, the central portion of said depression being crvedfoutwardly, and a packing ring of pliant material having normally flat and relatively broad side walls disposed in said depression, the thickness of said packing ring being such as to cause those portions disposed upon the outwardly curved portion of said depression to-lie beyond the surface of Y said piston side wall.

packing rings being such as to cause those por-J tions disposed in the portions of lesser depth of said depressions to lie beyond the surface of said piston side wall, said depressions being so larranged with respect to each other that the packing ring in one is' driven toward its said portion of lesser depth when the piston is moved in one direction and the packing ring in the other depression is driven toward its portion of lesser depth when the piston is moved in the opposite direction.

9. In a lubricant cartridge, a piston forming one end closure for said cartridge comprising a body having` a side wall adapted to lie substantially parallel to the inner side wall of the cartridge, a rubber packing ring disposed upon said piston side walll and adapted for sealing engagement with said cartridge wall, and a deposit o1' a gel of soda-rosin and soda-hydrofol soaps in glycerine disposed between said packing ring and the inner end of said piston. Y

10. In a lubricant cartridge, a piston lformi one end closure for said cartridge comprising a body having a side wall adapted to lie substantially parallel to the inner side wall of the cartridge and formed with a circumferential groove, a packing ring of material subject to deterioration in the presence of oil-soluble lubricant disposed in said groove and adapted for sealing engagement with said cartridge wall, and a-deposit of a gel of soap in polyhydroxyl alcohol disposed in said groove between said packing ring and the head wall of said piston.

11. A piston for lubricant cartridges having a substantially cylindrical side wall traversed by a circumferential depression, a portion of the bottom o1' said depression being curved outwardly longitudinally, a resilient packing ring in said depression and extending over said outwardly curved portion, whereby said packing assumes a convex form, and means lying between the packing and the inner end of the piston to protect the packing. ,4

' HARRY R. TEAR. 

